private void UpdateRingThumb()
{
if (_ringThumb == null)
{
return;
}
if (_containerGrid.ActualHeight <= 2 * (RingThickness + ThumbBorderThickness) ||
_containerGrid.ActualWidth <= 2 * (RingThickness + ThumbBorderThickness))
{
return;
}
//VisualTreeDebugger2.DebugVisualTree(_ringThumb, true);
// Hue ring needs to be smaller than available container space so the thumb fits
var hueRingSize = Math.Min(
_containerGrid.ActualWidth - 2 * ThumbBorderThickness,
_containerGrid.ActualHeight - 2 * ThumbBorderThickness);
//if (_ringThumb.Width != hueRingSize + 2 * ThumbBorderThickness)
{
_ringThumb.Width = hueRingSize + 2 * ThumbBorderThickness;
_ringThumb.Height = hueRingSize + 2 * ThumbBorderThickness;
_ringThumb.BeginUpdate();
// Half of the thumb border stroke goes outside the radius and the other half goes inside,
// so radius needs to be 0.5 border thickness larger than the hue ring's outer radius.
// Less 1 to make sure there is an overlap.
_ringThumb.Center =
new Point(
hueRingSize / 2 + ThumbBorderThickness,
hueRingSize / 2 + ThumbBorderThickness);
_ringThumb.Radius = (hueRingSize + ThumbBorderThickness) / 2 - 1;
_ringThumb.InnerRadius = _ringThumb.Radius - RingThickness - ThumbBorderThickness + 2;
_ringThumb.StartAngle = this.Value - ThumbArcAngle / 2;
_ringThumb.EndAngle = this.Value + ThumbArcAngle / 2;
//_ringThumb.StartAngle = - ThumbArcAngle / 2;
//_ringThumb.EndAngle = ThumbArcAngle / 2;
_ringThumb.EndUpdate();
}
_ringThumb.Stroke =
new SolidColorBrush(
ColorExtensions.FromHsv(this.Value, 0.5, 1.0));
}